Halakhah zu Könige I 5:34

From the laws of the commandment is that which they, may their memory be blessed, said (Bava Metzia 5b) that one who denies a deposit is disqualified from testimony - and even though he did not make an oath. And they said in the Gemara, [this is] specifically when the witnesses say that the deposit is in his house at that time. Its details are elucidated in [scattered] places in Tracatate Shevuot (see Tur, Choshen Mishpat 94).